Cinnamon uses 3 kinds of themes:Cinnamon themes are just for the shell (panel, menu, etc.)Window themes are responsible for window borders.GTK+ themes are for the rest.I think you might overlook the Gtk theme setting under the Other theme tab. But Mint came with only a few GTK themes pre-installed, none of which is dark. So you will have to download some dark themes

Sorry for nuisance, but are GTK+ themes available for cinnamon yet?, when going to the main Cinnamon themes page there are only the same few themes, so do I need to go to Gnome look or do I wait for later version for gtk+ themes to be compatible?

I've been with KDE for the last year or so and have only just today tried the latest Mint after seeing a few vids on youtube showing the latest Cinnamon desktop, so this is my 1st look at it, hence needing to know about this.Thanks

gtk3 themes you have to find on the internet and download yourself. This old guide still applies for gtk themes: viewtopic.php?f=42&t=86813 (scroll down to section 4A), except you select the theme in Cinnamon Settings instead of Gnome Tweak Tool.

Thank you for this thread. That’s all I can say. You most definitely have made this forum into something special. You clearly know what you are doing, you’ve covered so many bases. Thanks!